The invention concerns a battery pack which comprises at least one battery module with a plurality of battery cells, wherein said battery cells of the at least one battery module are held together by means of at least one holding element.
Electrical energy can be stored by means of batteries. Batteries convert chemical reaction energy into electrical energy. Here we distinguish between primary batteries and secondary batteries. Primary batteries are only able to function once, whereas secondary batteries—also known as accumulators—are rechargeable. A battery comprises one or more battery cells.
In particular, so-called lithium-ion battery cells are used in an accumulator and have an anode and a cathode. They are distinguished amongst others by high energy density, thermal stability and an extremely low self-discharge rate. Lithium-ion battery cells may be used amongst others in motor vehicles, in particular in electric vehicles (EV), hybrid electric vehicles (HEV) and plug-in hybrid electric vehicles (PHEV).
A generic battery cell is disclosed in DE 10 2012 217 451 A1. The battery cell has a cell housing which is made for example from a metal. The cell housing is prismatic in design, in particular cuboid, and is configured so as to be pressure-resistant. The battery cell has a positive terminal and a negative terminal for electrical contacting.
Several battery cells may be combined mechanically into a battery module. The battery cells are also connected together electrically. The terminals of the battery cells are connected together electrically by means of cell connectors.
Several battery modules may be combined into a battery pack and arranged in a common housing. The battery modules are also connected together electrically. Each terminal of the battery cell located at the edge of the battery module is electrically connected by means of a contact element to a terminal of a battery cell of another battery modul
Document DE 10 2009 035 494 A1 discloses a battery which is provided in particular for use as a traction battery in a vehicle. The battery comprises several battery cells arranged next to each other in a block or stack and connected together electrically. The battery cells are held together by means of peripheral clamping straps. The clamping straps surround not only the battery cells but also a cover plate, a cooling plate and two pole plates.
Document DE 10 2013 112 731 A1 discloses a battery for a motor vehicle. Several battery cells are combined into a battery module, and several battery modules form a battery layer. Such a battery layer is placed in a housing tray. Because of the shape of the battery tray, the arrangement of the battery layer in the housing tray is necessarily predefined.
Document DE 10 2013 206 503 A1 discloses a battery module for a motor vehicle. The battery module comprises several battery cells arranged in a holding device. The holding device comprises fixing tabs by means of which a cooling plate can be attached to the holding device. The holding device furthermore comprises a cover on which fixing elements are arranged. By means of the fixing elements, the cover is attached by form fit to the housing of the holding device, and the battery cells are therefore fixed inside the holding device.
Document DE 10 2012 219 778 A1 discloses a battery module, in particular for use in a vehicle, which comprises several battery cells. The battery cells are arranged next to each other and connected together electrically. The battery module comprises a multipiece housing in which the battery cells are held. A conductor rail with a tab-like protruding portion is provided for electrical connection of the battery module.